package SQL::Translator::Parser::Access;

# -------------------------------------------------------------------
# $Id: Access.pm,v 1.2 2004-07-30 21:56:18 kycl4rk Exp $
# -------------------------------------------------------------------
# Copyright (C) 2002-4 SQLFairy Authors
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; version 2.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
# 02111-1307  USA
# -------------------------------------------------------------------

=head1 NAME

SQL::Translator::Parser::Access - parser for Access as produced by mdbtools

=head1 SYNOPSIS

  use SQL::Translator;
  use SQL::Translator::Parser::Access;

  my $translator = SQL::Translator->new;
  $translator->parser("SQL::Translator::Parser::Access");

=head1 DESCRIPTION

The grammar derived from the MySQL grammar.  The input is expected to be 
something similar to the output of mdbtools (http://mdbtools.sourceforge.net/).

=cut

use strict;
use vars qw[ $DEBUG $VERSION $GRAMMAR @EXPORT_OK ];
$VERSION = sprintf "%d.%02d", q$Revision: 1.2 $ =~ /(\d+)\.(\d+)/;
$DEBUG   = 0 unless defined $DEBUG;

use Data::Dumper;
use Parse::RecDescent;
use Exporter;
use base qw(Exporter);

@EXPORT_OK = qw(parse);

# Enable warnings within the Parse::RecDescent module.
$::RD_ERRORS = 1; # Make sure the parser dies when it encounters an error
$::RD_WARN   = 1; # Enable warnings. This will warn on unused rules &c.
$::RD_HINT   = 1; # Give out hints to help fix problems.

$GRAMMAR = q!

{ 
    my ( %tables, $table_order, @table_comments );
}

#
# The "eofile" rule makes the parser fail if any "statement" rule
# fails.  Otherwise, the first successful match by a "statement" 
# won't cause the failure needed to know that the parse, as a whole,
# failed. -ky
#
startrule : statement(s) eofile { \%tables }

eofile : /^\Z/

statement : comment
    | use
    | set
    | drop
    | create
    | <error>

use : /use/i WORD ';'
    { @table_comments = () }

set : /set/i /[^;]+/ ';'
    { @table_comments = () }

drop : /drop/i TABLE /[^;]+/ ';'

drop : /drop/i WORD(s) ';'
    { @table_comments = () }

create : CREATE /database/i WORD ';'
    { @table_comments = () }

create : CREATE TABLE table_name '(' create_definition(s /,/) ')' ';'
    { 
        my $table_name                       = $item{'table_name'};
        $tables{ $table_name }{'order'}      = ++$table_order;
        $tables{ $table_name }{'table_name'} = $table_name;

        if ( @table_comments ) {
            $tables{ $table_name }{'comments'} = [ @table_comments ];
            @table_comments = ();
        }

        my $i = 1;
        for my $definition ( @{ $item[5] } ) {
            if ( $definition->{'supertype'} eq 'field' ) {
                my $field_name = $definition->{'name'};
                $tables{ $table_name }{'fields'}{ $field_name } = 
                    { %$definition, order => $i };
                $i++;
        
                if ( $definition->{'is_primary_key'} ) {
                    push @{ $tables{ $table_name }{'constraints'} },
                        {
                            type   => 'primary_key',
                            fields => [ $field_name ],
                        }
                    ;
                }
            }
            elsif ( $definition->{'supertype'} eq 'constraint' ) {
                push @{ $tables{ $table_name }{'constraints'} }, $definition;
            }
            elsif ( $definition->{'supertype'} eq 'index' ) {
                push @{ $tables{ $table_name }{'indices'} }, $definition;
            }
        }

        1;
    }

create : CREATE UNIQUE(?) /(index|key)/i index_name /on/i table_name '(' field_name(s /,/) ')' ';'
    {
        @table_comments = ();
        push @{ $tables{ $item{'table_name'} }{'indices'} },
            {
                name   => $item[4],
                type   => $item[2] ? 'unique' : 'normal',
                fields => $item[8],
            }
        ;
    }

create_definition : constraint 
    | index
    | field
    | comment
    | <error>

comment : /^\s*--(.*)\n/ 
    { 
        my $comment =  $1;
        $return     = $comment;
        push @table_comments, $comment;
    }

field : field_name data_type field_qualifier(s?) reference_definition(?)
    { 
        $return = { 
            supertype   => 'field',
            name        => $item{'field_name'}, 
            data_type   => $item{'data_type'}{'type'},
            size        => $item{'data_type'}{'size'},
            constraints => $item{'reference_definition(?)'},
        } 
    }
    | <error>

field_qualifier : not_null
    { 
        $return = { 
             null => $item{'not_null'},
        } 
    }

field_qualifier : default_val
    { 
        $return = { 
             default => $item{'default_val'},
        } 
    }

field_qualifier : auto_inc
    { 
        $return = { 
             is_auto_inc => $item{'auto_inc'},
        } 
    }

field_qualifier : primary_key
    { 
        $return = { 
             is_primary_key => $item{'primary_key'},
        } 
    }

field_qualifier : unsigned
    { 
        $return = { 
             is_unsigned => $item{'unsigned'},
        } 
    }

field_qualifier : /character set/i WORD
    {
        $return = {
            character_set => $item[2],
        }
    }

reference_definition : /references/i table_name parens_field_list(?) match_type(?) on_delete_do(?) on_update_do(?)
    {
        $return = {
            type             => 'foreign_key',
            reference_table  => $item[2],
            reference_fields => $item[3][0],
            match_type       => $item[4][0],
            on_delete_do     => $item[5][0],
            on_update_do     => $item[6][0],
        }
    }

match_type : /match full/i { 'full' }
    |
    /match partial/i { 'partial' }

on_delete_do : /on delete/i reference_option
    { $item[2] }

on_update_do : /on update/i reference_option
    { $item[2] }

reference_option: /restrict/i | 
    /cascade/i   | 
    /set null/i  | 
    /no action/i | 
    /set default/i
    { $item[1] }  

index : normal_index
    | fulltext_index
    | <error>

table_name   : NAME

field_name   : NAME

index_name   : NAME

data_type    : access_data_type parens_value_list(s?) type_qualifier(s?)
    { 
        $return        = { 
            type       => $item[1],
            size       => $item[2][0],
            qualifiers => $item[3],
        } 
    }

access_data_type : /long integer/i { $return = 'Long Integer' }
    | /text/i { $return = 'Text' }
    | /datetime (\(short\))?/i { $return = 'DateTime' }
    | /boolean/i { $return = 'Boolean' }
    | WORD

parens_field_list : '(' field_name(s /,/) ')'
    { $item[2] }

parens_value_list : '(' VALUE(s /,/) ')'
    { $item[2] }

type_qualifier : /(BINARY|UNSIGNED|ZEROFILL)/i
    { lc $item[1] }

field_type   : WORD

create_index : /create/i /index/i

not_null     : /not/i /null/i { $return = 0 }

unsigned     : /unsigned/i { $return = 0 }

default_val : /default/i /'(?:.*?\\')*.*?'|(?:')?[\w\d:.-]*(?:')?/
    {
        $item[2] =~ s/^\s*'|'\s*$//g;
        $return  =  $item[2];
    }

auto_inc : /auto_increment/i { 1 }

primary_key : /primary/i /key/i { 1 }

constraint : primary_key_def
    | unique_key_def
    | foreign_key_def
    | <error>

foreign_key_def : foreign_key_def_begin parens_field_list reference_definition
    {
        $return              =  {
            supertype        => 'constraint',
            type             => 'foreign_key',
            name             => $item[1],
            fields           => $item[2],
            %{ $item{'reference_definition'} },
        }
    }

foreign_key_def_begin : /constraint/i /foreign key/i 
    { $return = '' }
    |
    /constraint/i WORD /foreign key/i
    { $return = $item[2] }
    |
    /foreign key/i
    { $return = '' }

primary_key_def : primary_key index_name(?) '(' name_with_opt_paren(s /,/) ')'
    { 
        $return       = { 
            supertype => 'constraint',
            name      => $item{'index_name(?)'}[0],
            type      => 'primary_key',
            fields    => $item[4],
        };
    }

unique_key_def : UNIQUE KEY(?) index_name(?) '(' name_with_opt_paren(s /,/) ')'
    { 
        $return       = { 
            supertype => 'constraint',
            name      => $item{'index_name(?)'}[0],
            type      => 'unique',
            fields    => $item[5],
        } 
    }

normal_index : KEY index_name(?) '(' name_with_opt_paren(s /,/) ')'
    { 
        $return       = { 
            supertype => 'index',
            type      => 'normal',
            name      => $item{'index_name(?)'}[0],
            fields    => $item[4],
        } 
    }

fulltext_index : /fulltext/i KEY(?) index_name(?) '(' name_with_opt_paren(s /,/) ')'
    { 
        $return       = { 
            supertype => 'index',
            type      => 'fulltext',
            name      => $item{'index_name(?)'}[0],
            fields    => $item[5],
        } 
    }

name_with_opt_paren : NAME parens_value_list(s?)
    { $item[2][0] ? "$item[1]($item[2][0][0])" : $item[1] }

UNIQUE : /unique/i { 1 }

KEY : /key/i | /index/i

table_option : WORD /\s*=\s*/ WORD
    { 
        $return = { $item[1] => $item[3] };
    }

CREATE : /create/i

TEMPORARY : /temporary/i

TABLE : /table/i

WORD : /\w+/

DIGITS : /\d+/

COMMA : ','

NAME    : "`" /\w+/ "`"
    { $item[2] }
    | /\w+/
    { $item[1] }

VALUE   : /[-+]?\.?\d+(?:[eE]\d+)?/
    { $item[1] }
    | /'.*?'/   
    { 
        # remove leading/trailing quotes 
        my $val = $item[1];
        $val    =~ s/^['"]|['"]$//g;
        $return = $val;
    }
    | /NULL/
    { 'NULL' }

!;

# -------------------------------------------------------------------
sub parse {
    my ( $translator, $data ) = @_;
    my $parser = Parse::RecDescent->new($GRAMMAR);

    local $::RD_TRACE  = $translator->trace ? 1 : undef;
    local $DEBUG       = $translator->debug;

    unless (defined $parser) {
        return $translator->error("Error instantiating Parse::RecDescent ".
            "instance: Bad grammer");
    }

    my $result = $parser->startrule($data);
    return $translator->error( "Parse failed." ) unless defined $result;
    warn Dumper( $result ) if $DEBUG;

    my $schema = $translator->schema;
    my @tables = sort { 
        $result->{ $a }->{'order'} <=> $result->{ $b }->{'order'}
    } keys %{ $result };

    for my $table_name ( @tables ) {
        my $tdata =  $result->{ $table_name };
        my $table =  $schema->add_table( 
            name  => $tdata->{'table_name'},
        ) or die $schema->error;

        $table->comments( $tdata->{'comments'} );

        my @fields = sort { 
            $tdata->{'fields'}->{$a}->{'order'} 
            <=>
            $tdata->{'fields'}->{$b}->{'order'}
        } keys %{ $tdata->{'fields'} };

        for my $fname ( @fields ) {
            my $fdata = $tdata->{'fields'}{ $fname };
            my $field = $table->add_field(
                name              => $fdata->{'name'},
                data_type         => $fdata->{'data_type'},
                size              => $fdata->{'size'},
                default_value     => $fdata->{'default'},
                is_auto_increment => $fdata->{'is_auto_inc'},
                is_nullable       => $fdata->{'null'},
                comments          => $fdata->{'comments'},
            ) or die $table->error;

            $table->primary_key( $field->name ) if $fdata->{'is_primary_key'};
        }

        for my $idata ( @{ $tdata->{'indices'} || [] } ) {
            my $index  =  $table->add_index(
                name   => $idata->{'name'},
                type   => uc $idata->{'type'},
                fields => $idata->{'fields'},
            ) or die $table->error;
        }
    }

    return 1;
}

1;

# -------------------------------------------------------------------
# Where man is not nature is barren.
# William Blake
# -------------------------------------------------------------------

=pod

=head1 AUTHOR

Ken Y. Clark E<lt>kclark@cpan.orgE<gt>.

=head1 SEE ALSO

perl(1), Parse::RecDescent, SQL::Translator::Schema.

=cut
